textproduct: Rapid City

KEY MESSAGES

- Near daily chances for thunderstorms continue into next week.

- At or above normal highs continue with high temps in the 80s and 90s through the weekend and well into next week.

UPDATE

Issued at 932 PM MDT Fri Jul 3 2026

Weak upper trough will continue to move across the region tonight with low chances for showers/storms across the northern half into Sat morning. Sufficient low level moisture, SE upslope flow, and weak capping will support shower/TS chances over the BH Sat afternoon. Sufficient CAPE and deep layer shear will be in place to support a few stronger cells. TS's will also be possible over scentral SD where much higher CAPE will be in place coupled with the tail end of LSA from the departing upper trough. Although TS chances will be highly conditional on whether capping can be overcome. Hot and dry Sunday, with thunderstorm chances returning Sunday night and Monday as a trough settles into the region.

DISCUSSION

(This Evening Through Friday) Issued at 1222 PM MDT Fri Jul 3 2026

Thunderstorms have begun. As of the 11AM, the recent storm activity has been mainly contained to the northern Black Hills with lingering leftover showers and storms in the western South Dakota plains. One storm cell produced impressive golf ball to ping pong ball sized hail in and near Spearfish.

For this afternoon through tonight, strong to severe storms chances will linger, especially around the Black Hills. Storm initiation and growth will likely happen from north to south along the outflow boundary that developed earlier. Large hail, strong winds, lightning, and locally heavy rainfall will accompany these storms.

Beyond the Black Hills, storms will track east to southeast through the afternoon. Another concern is storm development in eastern Wyoming and eastern Montana that would track into the area this evening. These storms could be strong to severe with strong winds being the main concern. Overnight storms will weaken and fade out.

This weekend is looking like a story with two very different chapters. Surface low pressure on the lee side of the Rockies will finally kick out eastward as an upper level trough slides eastwards along the northern edge of a high pressure building to our south. Once that trough and surface low move out, the ridge of high pressure will build over the CWA for Sunday.

This pattern will give the area storm chances Saturday into Saturday evening with afternoon temps in the 80s to near 90F. If we see any severe weather on Saturday, the latest guidance is putting the better chances of severe weather, around 10 to 30%, to the south in Nebraska and to the east closer to Iowa. A marginal risk for severe weather has been placed over the Black Hills and south.

Sunday is looking very different as that high pressure builds. Skies will be clear to mostly clear and dry as afternoon temps jump into the 90s to near 100F. Can't rule out pop up storms over and near the Black Hills though.

A quick glance at next week, the near daily chances for isolated to scattered afternoon thunderstorms continue. Temperatures will be at or above normal with highs in the 80s to 90s and overnight lows in the 60s.

AVIATION

(For the 12Z TAFS Through 12Z Sunday Morning) Issued At 512 AM MDT Sat Jul 4 2026

Overall a quieter day is expected today across northeast Wyoming and western South Dakota with high confidence in predominantly VFR conditions for aviation, and nearly clear skies for most areas. A few thunderstorms will still be possible this afternoon and evening from the Black Hills corridor southeastward into the south-central South Dakota plains, a few of which could be strong to severe and produce transient MVFR conditions. However, coverage should remain isolated. Timing today looks to be 1 PM to 7 PM for this potential. Probabilities remain below 30 percent for the moment at KRAP and thus have not included a PROB30 group, but have added SCT060 during the afternoon for nearby activity. South winds are expected to pick up and become gusty overnight tonight at KGCC.

UNR WATCHES/WARNINGS/ADVISORIES

SD...None. WY...None.